The present research will improve methods for the measurement of flight, fight and freezing reaction tendencies in the squirrel monkey. A standard repetitive shock delivery session will be used to elaborate functional interactions between cardiovascular and motor responses which are indices of escape avoidance and aggression reactions. Methods will be developed for the continous monitoring of heart rate and blood pressure from the squirrel monkey during the test session. Temporal patterning of behavioral responses and features of the cardiovascular record will be assessed. Additional experiments will explore the behavioral nature of the addiction process of nicotine. It has been established that nicotine produces reductions in reactions to noxious stimuli. The proposed experiments will develop intake routines of fluids during the repetitive shock delivery sessions and assess the effects of nicotine versus distilled water. After drinking routines are established the drink opportunity will be made contingent on a response by using an automatically removable water spout and a manipulandum such that entry of the spout into the chamber is contingent on a fixed-ratio schedule of responding on the manipulandum. Responding maintained by distilled water and nicotine will be assessed. BIBLIOGRAPHIC REFERENCES: HUTCHINSON, R.R. By-products of aversive control. In. W.K. Honig and J.E.R. Staddon (eds) Handbook of Operant Behavior, Englewood Cliffs, N.J.: Prentice-Hall, l976. Hutchinson, R.R., Emley, G.S. and Krasnegor, N.A. Effects of cocaine on aggressive behavior in mice, pigeons and squirrel monkeys. In. E.H. Ellinwood (ed) Cocaine and Other Stimulants, New York: Plenum Press, l976.